Method of making organic lithium compounds



United States atent METHOD OF MAKING ORGANIC LITHIUM COMPOUNDS Peter A. Asseif, Cleveland, Thomas W. Mastin, Willoughby, and Alan Rhodes, Euclid, Ohio, assignors to The gillbrizol Corporation, Wicklilfe, Ohio, a corporation of No Drawing. Application November 2, 1953, Serial No. 389,841

9 Claims. (Cl. 260-139) This invention relates to complex, organic materials which contain large amounts of lithium, and in particular to such complex organic salts which are completely soluble or dispersible in mineral oils.

' Prior art workers discovered that basic alkaline earth metal sulfonates of the structure shown below were more effective dispersants than the corresponding normal (neutral) sulfonates. It will be noted that such basic sulfonates, in addition to having a basic reaction, also have a relatively high percentage of metal. This is particularly true of the basic barium sulfonates because of the high atomic weight of the metal barium. Basic metal sulfonates of this type can be prepared by heating a normal metal sulfonate or sulfonic acid with a metal oxide or hydroxide, etc.

A subsequent development has been discovered recently in U. S. 2,616,924. In this patent there is disclosed a method for the preparation of a new type of oil-soluble, alkaline earth metal-bearing, complex organic material. Such materials prepared by the method of this patent may contain unusually high percentages of alkaline earth metal. These high metal-bearing compositions are useful in many applications, such as for example, the Waterproofing of films, stabilization of polyvinyl halide compositions, drying of natural oils, motor oil dispersants, etc.

The materials available from the process of the abovementioned patent are of relatively unknown structure. Two principal theories have been advanced as to their structure and they are as follows:

(1) The metal which is present in excess of that amount which can be accounted for as normal salt is merely peptized into a colloidal suspension by the normal metal salt.

(2) The metal which is present in excess of that amount which can be accounted for as normal salt is an integral apart of a chemical complex.

' The unusual properties of these high metal-containing complex materials have been thought by some to be a function of the relative amount of metal present. In connection with such an approach the metal present in oil-soluble form in a motor oil detergent or dispersant may be considered to exert its cleansing effect on the motor by means of a mild abrasive action. If such a concept is based on fact, then the more metal the better, and thus the efficacy of compositions containing a high percentage of metal.

The very presence of such large percentages of metal, even in apparently oil-soluble form, however, is a source of some concern. The metal complex, however oilsoluble, is nevertheless a potentially harmful deposit which may collect on one or more of the parts of an engine such as the rings, piston heads, or sparkplugs. The more metal there is present the greater is the possibility of such deposit collecting. For this reason some investi gators have accepted with reservation the advent of lot:

high metal-bearing compositions as lubricant additives. These investigators have in fact directed their efforts toward a search for a motor oil dispersant which contains no metal at all, a so-called ashless detergent.

Such ashless detergents as have been proposed heretofore have proved notably deficient in one or more essential characteristics, and have not yet shown any promise of competing with metal-containing detergents. Nevertheless the desirability of such a product provides an alluring goal for research.

The lithium metal complex materials of this invention employed in lubricating oil have a high percentage of metal; but a lower ash value than obtainable with corresponding alkaline earth metals. This is because of the low atomic weight of lithium. The molecular weight of barium ash, as barium sulfate, is 233, while the molecular weight of lithium ash, as lithium sulfate, is only 110. For this reason, the lithium complex materials of this invention, while possessing a high percentage of metal, have a low ash value.

An object of this invention, as a consequence, is the provision of an oil-soluble organic material which contains a relatively low percentage of metal. A more particular object is the provision of such a material which has dispersant or detergent qualities which adapt it for use in motor oils. A still more particular object is to provide a material which will possess the advantageous properties of oil-soluble complexes having a high percentage of metal, and in addition, provide the advantages associated with a material containing a relatively small percentage of metal.

Other and more specific objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

The above and other objects are achieved by the invention described herein, whereby hitherto unknown complex metal compositions are made available. Such complex metal compositions appear tohave the inherently beneficial properties which are a property of the hereinbefore mentioned metal complexes and at the same time they do not have an unduly high percentage of metal.

The complex lithium compositions of this invention are prepared by combining one or more inorganic lithium compounds with at least one oil-soluble organic acid, or lithium salt thereof, in the presence of at least one organic compound, which for convenience, may be referred to as a promoter.

In a more particular consideration the invention relates to products of 'the process comprising the reaction of one or more basically-reacting inorganic lithium compounds with at least one oil-soluble organic acid, or lithium salt thereof, such reaction being facilitated by the action of a promoter.

In a still more specific aspect the present invention can be described as the product prepared by the process which comprises preparing and mixing a mass which, at 50 C., at least 50% of the total mass is in the liquid state and in which mass the active components consist of:

(A) At least one oil-soluble organic acid compound containing at least 12 carbon atoms in the molecule selected from the class consisting of aliphatic and cyclic: sulfur acids, carboxylic acids, phosphorus acids, the thioacids corresponding to any of the foregoing acids and the lithium metal salts of any of said acids;

(B) At least one organic compound selected from the class consisting of: (l) the lithium metal salts of tautomeric organic salt-forming compounds, said tautomeric organic salt-forming compounds having: (a) an ionization constant in water, within the range from about 1' 10- to about 1x1O- at about C.; (b) a water solubility at C. of at least 0.0005 and (c) in saturated aqueous solutions at about 25 C. a pH of less than 7; and (2) tautomeric organic compounds which form the lithium salts of (1); the relative amounts of A and B used being of the range of from about 1 equivalent of A to about 10 equivalents of B to about 10 equivalents of A to about 1 equivalent of B;

(C) At least one basically reacting inorganic lithium metal compound in an amount such that there are present in the mass substantially more than 1 equivalent of lithium metal, including the lithium metal present in the remaining components, per equivalent of A plus B; and

(D) Water, in an amount equal to at least about .1 mole per mole of (C); maintaining the mass at a temperature and for a period of time suflicient to drive ofi substantially all free water and Water of hydration which may be present, and form the complex lithium composition.

The product obtained from the above process may then be treated as indicated below:

I. The product may be treated, preferably prior to filtration, with a relatively acidic inorganic reagent, which has an ionization constant greater than that of the organic compound of (B), in an amount sufilcient to liberate a substantial proportion of said organic compound of (B).

' II. At least a portion of the liberated organic compound of (B) may be removed from the reaction mass.

In order to facilitate a more explicit understanding of the invention the following description is subdivided under separate subject headings.

The novel products of this invention are available from a particularly simple process. The physical manipulations involved are merely those of mixing and heating specified ingredients, usually at about the reflux temperature of water, then removing the water by suitable means. Optionally the product of such a process may be modified by treatment with a relatively acidic reagent so as to liberate at least a portion of the anion of the promoter from its lithium salt.

Customarily the mixing of ingredients is carried out at room temperature. The resulting mixture which invariably contains some water isthen heated, usually for one to two hours at reflux ternperature. The period of such heating is not critical and the time may be extended well I beyond two hours without untoward effect. If a lower temperature than C. is desired, the time required would, of course, necessarily be lengthened; and correspondingly the use of a higher temperature, as in the case of a high pressure reaction, would allow a shorter time.

Removal of water may be achieved by distillation. The distillation may be carried out either at atmospheric or reduced pressure. Usually for reasons of economy it is conducted at atmospheric pressure. In some cases, where for example there might be reason to suspect instability of one or more of the ingredients or of a. particular product, this removal of water may be effected by a distillation at reduced pressure. In the usual process of the invention, however, the bulk of the water is removed by atmospheric distillation; the product mixture then is further substantially dehydrated by heating for a short period of time at l50l60 C.

The product of such a process as described above con tains a relatively large atomic proportion, but a relatively small weight percentage of lithium. Depending on whether or not the lithium complex has been treated with an acidic reagent, the complex may vary from substantially neutral to highly basic, as determined by titrimetry with phenolphthalein indicator according to ASTM procedure D-974 48T. The acid treatment converts the I lithium base to a salt which does not titrate under the titration procedure given above.

In many instances a highly basic product is quite satisfactory. In other cases, however, a substantially neutral complex is desirable. A- produet modified by acid treatment is sometimes more stable than its basically reacting chemical precursor. Furthermore, it is possible to incorporate a larger amount of lithium into the oil-soluble complex material when this optional acid treatment is performed.

Modification of a highly basic lithium complex material with a relatively acidic reagent may be carried out within a wide temperature range, and since it is conducted after the drying step, the temperature of the last stage of drying, i. e. -160 C., is usually the temperature at which this treatment is effected. Laboratory studies indicate that optimum results are secured in the acid-treatment step when a small proportion of water, e. g. from about 0.1% to about 1.5% in the preferred instance, still remains in the process mass. Should the process mass contain less than about 0.1% water after the drying operation, it is usually desirable to introduce a small proportion of water to facilitate the acid-treatment. This water may be introduced either as a liquid or as steam.

Finally the acid-treated product may be filtered, usually through a filter aid. The filtration removes solid contaminants such as the inorganic impurities in the basic inorganic lithium compound used as one of the starting materials. The filtration in all instances proceeds at a convenient rate to give the desired complex in good yield.

Oil-soluble organic acid compounds The class of compounds falling under this heading is comprised largely of high molecular weight carboxylic acids, sulfur acids, phosphorus acids, and the thio acids of any of these. It should be pointed out that the lithium salts of these acids may be used as starting materials in the process of this invention as well as the acids themselves. Thus the term organic acid compounds is intended to embrace the aforementioned organic acids, their lithium salts, and mixtures of said acids and salts.

The carboxylic acid compounds may be selected from among the fatty acids, naphthenic acids, and alkylated aromatic acids; and the lithium salts of the foregoing. These include, as specific examples, lauric, myristic, palmitic, olcic, stearic, linoleic, linolenic, eleostearic, and tall oil acids; wax-substituted benzoic, naphthoic, etc. acids; cetyl cylohexane carboxylic, dilauryl decahydronaphthalene carboxylic acids. Also, as indicated above, the thio-substituted derivatives of these acids may be used. These include in a general way compounds of the structural formulas shown above, where R is a high molecular weight hydrocarbon radical.

Particular types of sulfur acid compounds are those in which sulfur is the acid forming element, and includes sulfonic acids, sulfuric monoesters, sulfinic acids, sulfenic acids, thiosulfonic acids, and sulfamic acid; and the lithium salts of the foregoing. Of these it is preferred to employ the sulfonic acid compounds because of their economic availability. The aromatic sulfonic acids being most readily available, are of special interest. Specific examples of suitable sulfonic acids include the following: mahogany sulfonic acids, petrolatum sulfonic acids, monoand polywax substituted: naphthalene sulfonic, phenol sulfonic, diphenyl ether sulfonic, diphenyl ether disulfonic, naphthalene disulfide sulfonic, naphthalene disulfide disulfonic, diphenylamine disulfonic, diphenylamine sulfonic, thiophene sulfonic, alphachloronaphthalene sulfonic acids, etc.; cetyl chlorobenene sulfonic acids, cetyl phenol sulfonic acids, cetyl phenol disulfide sulfonic acids, cetyl phenol monosulfide sulfonic acids, dilauryl beta-naphthanol sulfonic acid, etc.; paraflin wax sulfonic acids, tetraisobutylene sulfonic acids, petroleum naphthene sulfonic acids, waxsubstituted cyclohexyl sulfonic acids; polydodecyl benzene sulfonic acids, etc.

Concerning the sulfonic acids the term "petroleum sulfonic, acid as used in this specification is intended to denote the oil-soluble sulfonic acids which are derived from petroleum, usually by treatment with sulfuric acid, oleum, sulfur trioxide, etc.

The organic phosphorus acid compounds contemplated as starting materials in the process of this invention include triand pentavalent phosphorus acids and the corresponding thio acids; and the lithium salts thereof.

Such acid compounds include the acid-esters of phosphorous, phosphoric, thiophosphoric, and thiophosphorous 'acids; and the lithium salts thereof. Of particular interest are the acid-esters. of dithiophosphoric acids, especially the acid-diesters of these acids. Specific examples of acid-esters of phosphorus acid include dicapryl dithiophosphoric acid, didodecyl dithiophosphoric acid, di-(waxphenyl) dithiophosphoric acid, didodecyl phosphoric acid, etc.

Also useful as starting materials for the production of metal complexes are the pentavalent organic, acids of phosphorus which contain at least one carbon-tophosphorus bond; i. e., those acids of the general formula:

(XH)3n wherein X and X are oxygen or sulfur, R is an organic radical bonded to phosphorus through a carbon atom, n is 1 or 2, and Rn contains a total of at least 12 carbon atoms. As stated supra, the lithium salts of such acids are also intended. I

When n is 2, there are, of course, two organic radicals present. Such radicals may be the same or dififerent; for example, R2 may represent two octyl radicals or a decyl radical and a hexyl radical.

, Other useful carbon-to-phosphorus bonded pentavalent organic' acids of phosphorus, but whose exact structures have not yet been ascertained, are the thio-acids prepared from aliphatic, cycloaliphatic and/or aromatict compounds which are devoid of hydroxyl, sulfhydryl, and keto groups by treating such compounds with at least one sulfurizing and phosphorizing reagent, such as PSCl-s, PzSs, P4S1, P433, P485, PzSs plus sulfur, PCla plus sulfur, elemental phosphorus plus sulfur, and the like, and optionally further treating with a hydrolyzing agent such as water, steam, and/ or metallic base. The preparation of such materials is disclosed in U. S. Patents Nos. 2,316,085; 2,316,086; 2,316,087; 2,316,088; 2,316,089; 2,316,091; 2,316,078; 2,316,079; 2,316,080; 2,316,081; 2,316,082; 2,316,083; 2,316,084; and 2,367,468.

Typical organic starting materials for the production of these thio-phosphorus acids are given hereinbelow:

Lubricating oil fractions, especially those of high aromaticity: Petrolatum Paraffin wax Paraffin oil Petroleum naphthene White oil Gas oil Abietane Cycloaliphatic hydrocarbons and their alkylated deriva-.

tives, e. g.:

Cyclohexane Methyl-cyclohexane Di-methyl-cyclohexanes Ethyl-cyclohexane Butyl-cyclohexanes Hexyl-cyclohexanes 6 'Decahydronaphthalene Cetyl-cyclohexane Bis-(diisobutyl) cyclohexanes The alkylated cyclopentanes, e. g.:

Ethyl-cyclopentane- Paraffin wax substituted cyclopentane' The alkylated decahydro-naphthalenes, e. g.:

'Di-ethyl decahydronaphthalene di-lauryl decahydronaphthalenes Aliphatic hydrocarbons, e. g.:

Hexanes Heptanes Octanes, e. g.:

n-Octane Diisobutane Decanes Dodecanes 1 Mixtures of the lower aliphatic hydrocarbons such as those found in e. g.:

Gasoline Kerosene Naphtha Octadecane Eicosane 'Tetracosane Pentacosane Heptacosane Triacontane Aromatic hydrocarbons and their alkylated derivatives,

e. g.; Benzene Toluene Xylenes Ethyl-benzene Amyl-benzenes Octyl-benzenes Naphthalene Methyl-naphthalenes Ethyl-naphthalenes Butyl-naphthalenes Anthracene Methyl-anthracenes Diphenyl Terphenyl The higher alkylated benzenes, e. g.:

Paraflin wax substituted benzene Monoand poly-(triisobutyl) benzenes Monoand poly-(tetraisobutyl) benzenes The higher alkylated naphthalenes, e. g.:

Petroleum substituted naphthalene Paraflin wax substituted naphthalene Terpene polymers, e. g.:

Polymerized turpentine Polymerized menthenes Alkylene andv alkadiene polymers, e. g.:

Polyethylenes Polypropylenes Polybutenes Polyisoprenes, e. g. natural rubber Polybutadienes Polycaprylenes Co-polymers, e. g.:

Styrene-butadiene co-polymers Styrene-methyl acrylate co-polymers p Methyl alpha methyl-styrene-vinyl chloride copolymers Of the foregoing starting materials for the preparation of thio-phosphorus acids, the olefin polymers having a molecular weight range from 300 to 5000 are preferred. The thiophosphorus acids may be obtained by reacting P255, for example, with a polymer of the type hereindescribed at a temperature of from about C. to about 300 C., and preferably from about C. to about 275 C. It is advantageous to maintain a non-oxidizing atmosphere, such as, for example, an'atmosphere of nitrogen, above the reaction mixture. From about 1% to about 50% and preferably from about 5% to about 25% of the P255 may be used. Usually it is preferable to use an amount of P285 that will completelyreact with the polymer, so that no purification is necessary. However, excess P255 may be used and separated from the product after the heating is discontinued, by filtering or by diluting with a solvent such as hexane, filtering, and distilling off the solvent. The reaction. product may be further treated by blowing with steam or nitrogen at an elevated temperature of from about 90 C. to about 300 C. to improve the odor thereof.

Acid compounds of phosphorus having at least one carbon-to-phosphorus bond, when used in admixture with at least one oil-soluble sulfonic acid compound, have been found to provide highly useful starting materials for producing our metal complexes. Particularly valuable complex metal compositions for some uses, as for example in lubricants, are obtained when using as an oilsoluble organic acid the combination of petroleum sulfonate and the carbon-to-phosphorus bonded acid obtained by treating polybutylenes in the molecular weight range of 300 to 5000 with a mixture of P255 and sulfur.

The organic acids discussed herein are restricted to those acids whose lithium salts are soluble in mineral oil. Such a restriction excludes low molecular weight acids, such as acetic, propionic, ethane sulfonic, etc. acids. Usually a total of 12 or more carbon atoms in the organic residue are sufficient to confer such oil-solubility upon an acid, although it should be pointed out that oil-solubility of the lithium salts is the limiting criterion for organic acids.

Promoter Promoters have been defined hereinbefore as organic compounds, separate and distinct from the oil-soluble organic acid compound, selected from the class consisting of organic tautomeric compounds and the lithium salts of said tautomeric compounds. The term tautomeric compound is interpreted in the light of chapter 14, Tautomerism, in G. W. Whelands Advanced Organic Chemistry, 2nd ed, John Wiley and Sons, New York. Thus, tautomeric compounds embrace such classes as enols, phenols, irnides, amides, oximes, primary and secondary aliphatic aci-nitro compounds, etc. The enols, phenols, and aci-nitro compounds are preferred because of their availability. Because of their relatively low cost phenols are used more extensively as promoters than the others.

Specific examples of promoters include phenol and alkylated phenols such as isopropyl phenol, tert-butyl phenol, sec-amyl phenol, iso-octyl (diisobutyl) phenol, capryl phenol, nonyl phenol, decyl phenol, and n-hexyl phenol; other substituted phenols such as o-chlorophenol, p-chlorophenol, p-nitrophenol, and p-methoxyphenol; polyhydroxy compounds such as resorcinol, catechol and phloroglucinol; enolic compounds such as 'acetylacetone, acetoacetic ester, diethyl malonate, benzoylacetone, biacetyl, acetoacetophenone, and benzyl methyl ketone; imides such as succinimide, phthalimide and glutarimide; amides such as acetamide; acetanilide, benzamide, and ochlcrobenzamide; oximes such as acetone oxime, acetophenone oxime, camphor oxime, diisobutyl ketone oxime, isophorone oxime and benzaldehyde oxime; primary and secondary aliphatic nitro compounds such as nitromethane, l-nitropropane, 2-nitropropane, nitroparafiin wax and 2-nitrobutane.

The organic salt-forming promoters preferably have a pH of less than 7 in aqueous solutions at about 25 C., are water soluble to the extent of at least 0.0,005% at 50 C., and desirably possess an ionization constant within the range from about 1 10 to about 1X10", and most. desirably at least 1X10" in water at 25C.

Basic inorganic lithium compounds The basic reagents used to impart to the mass lithium metal may be broadly defined as inorganic lithium'compounds and comprise such compounds as lithium metaborate, lithium hydroxide, lithium oxide, lithium sulfide, lithium 'hydrosu'lfide, lithium amide, and the hydrated forms of any of these basic compounds. Of the inorganic lithium compounds, those having a water solubility of at least 0;0003% at 50 C. are preferred. Inorganic lithium metal compounds employed in the process should have a pH greater than 7 in water at 25 C. The lithium oxides, sulfides, hydroxides, and hydrosulfides are preferred,-with special preference given lithium hydroxide.

Acid treating agent The relatively acidic reagent or acid-treating agent" referred to hereinbefore is defined most conveniently by reference to its ionization constant and the relationship of that value with the ionization constant of the promoter. In all cases the ionization constant of the acid-treating agent should be significantly greater than that of the promoter, so that it can perform the function of liberating at least a portion of the anions of the promoter from its lithium salt. This acid liberation-can'be illustrated by the following equation wherein T is promoter anion, Li is lithium, is hydrogen, and A is the anion of the acidtreating agent:

The LiA, or lithium salt of the acid agent, is retained in the complex in oil-soluble form. The liberated, metalfree promoter (TH) may be permitted to remain in the complex or at least a portion thereof may be removed, as, for example, by distillation. Compounds which find widest use as acid-treating agents in the practice of this invention are those which are in the gaseous state although liquid and even solid acidic reagents may be used. Particularly useful acidic reagents, however, include such materials as carbon dioxide, carbon disulfide, hydrogen sulfide, sulfur dioxide, sulfur trioxide, carbon oxysulfide, etc. Of these, carbon dioxide is preferred because of its economy, ease of handling, and the utility of products prepared with it.

Relative amounts of ingredients As a matter of convenience in discussing the relative amounts of ingredients that can be used in the process of this invention the amount of oil-soluble organic acid shall be regarded as one mole. Thus all quantities of other starting materials, such as the promoter, the basic inorganic lithium compound, water, etc., shall be regarded as multiples of this unit.

The promoter is effective in its promoting action in quite small amounts. As little as 0.1 mole (per 1.0 mole of oil-soluble organic acid) of promoter has been found to have a significant promoting action in the process and the invention contemplates the use of such amounts. At the other end of the scale of proportions there is actually no limit to the relative amount of promoter which may be used, other than considerations of cost and ultimate end use of the complex product; there should of course be some oil-soluble organic acid using as a starting material, so that the amount of promoter does not reach infinity. As a practical consideration in the light of the scope of the invention it is intended to use as much as 10.0 moles (per mole of oil-soluble organic acid) of promoter.

The quantity of basic, inorganic lithium compound which may be used should be sufiicient so that there is present in the mass more moles of lithium, than moles of oil-soluble organic acid plus promoter. Thus, if one mole of oil-soluble organic acid and one mole of promoter are used, then more than two moles of basic inorganic lithium compound must be used. It should be pointed out, that if the lithium salts of the oil-soluble organic acid and (or) the promoter are used as starting ingredients then the amount of basic inorganic lithium compound may be reduced proportionately. Thus, if .one mole of the lithium salt of an oil-soluble organic acid, 0.5 mole of the lithium salt of a promoter and 0.5 mole of lithium-free promoter are used, then the quantity of basic inorganic lithium compound need exceed only 0.5 mole. In brief, there should be more than enough lithium in the product than is required to form the normal salts of the oil-soluble, organic acid and the promoter.

Water has been found to be an essential ingredient in the process of this invention. The water may be present in the form of a hydrated, basic inorganic lithium compound or it may be At least 0.1 mole of water per mole of basic inorganic lithium compound should be used and it is the normal practice to use considerably more than this minimum amount. Inasmuch as substantially all of the water is removed during the process, it is advisable not to use an unnecessarily large amount.

The optional use of a relatively acidic agent has the eflect of liberating from the product mass the metal-free promoter. In most cases and particularly where it is de sired to recover the promoter, the amount of acidic agent should be equivalent at least to the amount of total metal present in excess of the amount present as the normal salt of the oil-soluble acid.

The invention may be illustrated further by the various examples which follow. These examples serve to clarify certain parts of the invention and to indicate its application, but they should not be construed so as to limit the scope thereof. The term metal ratio used hereinafter is used to designate the ratio of total equivalents of lithium in the complex per equivalent of oil-soluble organic acid therein.

EXAMPLE 1 The following experiment, while it does not illustrate the invention directly, does serve to point up the nature of the invention in that it demonstrates the essentiality of the promoter in the process. The process of the invention is used, except that no promoter is present. The product contains only slightly more than the theoretical amount of lithium required to form the normal salt of the oil-soluble organic acid and clearly does not measure up to the requirements of the products of this invention.

A mixture of 636 grams (1.0 equivalent) of petroleum sulfonic acid, 413 grams of mineral oil, and 300 grams of water was heated to 70 C., then treated with 126 grams (3.0 equivalents) of lithium hydroxide monohydrate. The resulting mixture was heated at reflux temperature for an hour. The water was removed by distillation and the residue dehydrated further by heating at 150 C. for two hours. The dried product was filtered through a siliceous filter aid. The brown filtrate was shown by analyses to have the following:

Lithium content percent 0.9 Basic number 9 Metal ratio 1.15 Sulfate ash percent 7.22

EXAMPLE 2 A mixture of 2167 grams (3.26 um sulfonic acid, 1280 grams of mineral oil and 525 grams of water was treated at 70 C. with 150 grams (3.55 equivalents) of lithium hydroxide monohydrate, then heated at reflux temperature for one hour. To the product mixture there was added 404 grams (1.96 equivadded as such to the reaction mixture.

equivalents) of petrolek alents) of diisobutyl phenol and an additional 525 grams (12.45 equivalents) of lithium hydroxide monohydrate; this mixture was heated at reflux temperature for onehour, then was dried'by heating to C. over a period of three hours. The dried mixture was treated for two hours at 150 C. with carbon dioxide, then dried further by maintaining thistemperature for another hour. The mixture was filtered through a siliceous filter aid yielding a brown, oil-soluble liquid which was shown by analyses to have the following:

Lithium content percent 2.6

Basic number 9.7 Metal ratio 4.5

(4.54 moles) of polyisobutylene. added p-or-tionwise, a mixture of 672 grams (3.02 moles) of phosphorus pentasulfide and 84 grams (2.62 moles) of sulfur. The resulting mixture was heated at 205-215 C. for three hours, diluted with 1480 grams of oil, then treated at this temperature'with steam for 4.5 hours. The product was filtered through a filter aid, yielding a filtrate having the following:

Sulfur Percent 1.1 Phosphorus do 2.4 Acid number 63.5

, To 1764 grams (2,0 equivalents) of the above product there was added at 70 C. 300 ml. of 30% aqueous lithium hydroxide. This was heated at reflux temperature for 1.5 hours, then dried by distilling oif the water and heating at 150 ,C. for 1.5 hours. The product was filtered through a filter aid. The filtrate had the following:

Sulfur Percent 1.0 Phosphorus do 2.3 Lithium do; 0.9

Lithium content -Percent 2.34

Basic number 5.7

Metal ratio 4.3

' EXAMPLE 4 A mixture of 3225 grams (5.0 equivalents) of petroleum sulfonic acid, 620 grams (3.0 equivalents) of diisobutyl phenol, 3080 grams of mineral oil and 800 grams of Water was heated to 70 C., then treated with 1058 grams (25.2,equivalents) of lithium hydroxide monohydrate. This mixture was heated at reflux temperature for one hour, then dried by heatingto 150 C. Carbon dioxide was bubbled into the mixture at this temperature for one hour, then the mixture was filtered through a siliceous filter aid. The filtrate was a brown liquid, having the following analyses: Lithium content Per-cent' 2.2 Basic number 0.8 Metal rati 5.0 Sulfate ash Percent-.. 17.3

1 1 EXAMPLE A mixture of 666 grams (1.0 equivalent) of petroleum sulfonic acid, 457 grams of mineral oil, 208 grams (4.94 equivalents) of lithium hydroxide monohydrate, 54 grams (0.60 equivalent) of nitropropane, and 125 grams of water was heated at reflux temperature for two hours. The product was freed of water by heating to 150 C. over a period of three hours, then was treated for one hour at that temperature with carbon dioxide. The mixture was dried further by another hour of heating at 150 C., then filtered through a filter aid. The filtrate was a slightly viscous, brown liquid having the following:

1369 grams (1.0 equivalent) of an acid prepared sub- H stantia-lly in accordance with the procedure given in Patout No. Reissue 22,464, by treatment of polyisobutylene of an average molecular weight of 750 with P255, 124' grams (0.602 equivalent) of diisobutylphenol, and 225 ml. of Water were stirred at 70 C. and 208 grams (4.94'equivalents) of lithium hydroxide monohydrate were added there-to. After all of the lithium hydrate had been added, the whole was refluxed for 2 hours at about 100 C. and then gradually heated to 150 C. to remove substantially all of the water present. A vigorous current of carbon dioxide was then introduced into the process mass over a 4-hour period at about 150 C. Filtration of the mass yielded the desired lithium complex, a greenish-brown, oilsoluble liquid having the following analyses:

Percent phosphorus 1.29 Percent lithium 1.88 Neutralization No. (acidic) 1.0 Metal ratio 4.36

The utility of the products of this invention is demom strated by the results of a Buda diesel engine test:

The diesel engine employed in this test is a singlecylinder, liquid-cooled engine which develops 7.5 brakehorsepower at 1800 R. P. M. It is manufactured by the Buda Company of Harvey, Illinois, and bears the designation Model 1-BD-38.

The following conditions were adhered to in testing lubricants noted in the following table in the Buda engine:

Duration of test 100 hours.

Load 5 brake-horsepower.

Speed 1800 R. P. M.

Fuel type Diesel fuel oil containing about 0.4% naturally occurring sulfur.

Fuel consumption 3.05 pounds-per hour.

Lubricant temperature--- 175 F.

Coolant temperature 200 F.

Merit Overall rating for Lubri- I merit carbonacant Composition rating for oeous N 0. piston 1 deposits in top ring groove 2 1 SAE solvent-refined Mid-Oon- 45. 9 4. 6

, tinent motor oil. A,

2 (1)+1% of a mixture of 60 mole 51.9 6.3

percent zinc di-(4-rnethyl-seeamyl) dithiophosphate and 40 tnole percent zinc diisopropyl dithiophosphate, 40.0% solution in a low viscosity mineral oil. 3 (2) +1.82% of sulfate ,ash as the 69.7 6.2

product of Example 3.

l 100=perfectly clean. IO-perfectly clean.

i2 7 The present application is a continuation-in-part of the copending application, Serial No. 216,101, filed March 16, 1951.

Other modes of applying the principle of the inventionrnay be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed.

We therefore particularly point out and distinctly claim as our invention:

1. A process which'comprises preparing and mixing a mass in which at 50 C. at least 50% of the total mass is in the liquid state and in which mass the active components consist of: (a) an oil-soluble organic compound containing at least 12 carbon atoms selected from the class consisting of sulfonic and phosphorus thioic acids and the lithium saltsthereof, (b) from 0.1 to 10.0 equivalents of'a'n organic compound selected from the class consisting of enols, phenols and aci-nitro compounds and the lithium salts of said compounds, (0) a basically reacting inorganic lithium compound in an amount such that there is present in the mass substantially more than one equivalent of lithium, including the lithium present in the remaining components, per equivalent of (a) plus (b), and (d) at least 0.1 mole of water per mole of (c), and evaporating the water from the mass to form a lithium complex, and then bubbling carbon dioxide into the mass to liberate a substantial proportion of the organic compound of (b) from its lithium salt.

2. The process of claim 1 further characterized in that the organic compound of (b) is an alkyl-substituted phenolic compound.

3. The process of claim 1 further characterized in that the organic'compound of (b) is diisobutyl phenol.

4. The process of claim 1 further characterized in that the organic compound of (.b) is an aci-nitro compound.

5. The process of claim 1 further characterized in that the organic compound of (b) is nitropropane.

6. The process of claim 1 further characterized in that the oil-soluble organic compound of (a) is a petroleum sulfonic acid.

7. The process of claim 1 further characterized in that the oil-soluble organic compound of (a) is a polyolefinicphosphorus sulfide reaction product.

8. The process of claim 1 further characterized in that the oil-soluble organic compound of (a) is derived from the reaction of polyisobutylene with phosphorus pentasulfide.

9. The process of claim 1 further characterized in that the oil-soluble organic compound of (a) is prepared by the reaction of polyisobutylene having an average molecular weight of 750 with phosphorus pentasulfide.

References Cited in the file of this patent UNITED STATES PATENTS Re. 22,464 Kel'so et al. April 4, 1944 2,316,091 White -April 6, 1943 2,424,402 Loane et al July 22, 1947 2,442,915 Berger et al June 8, 1948 2,489,249 Adelson Nov. 29, 1949 2,616,924 Assefi et a1. Nov. 4, 1952 

1. A PROCESS WHICH COMPRISES PREPARING AND MIXING A MASS IN WHICH AT 50*C. AT LEAST 50% OF THE TOTAL MASS IS IN THE LIQUID STATE AND IN WHICH MASS THE ACTIVE COMPONENTS CONSIST OF: (A) AN OIL-SOLUBLE ORGANIC COMPOUND CONTAINING AT LEAST 12 CARBON ATOMS SELECTED FROM THE CLASS CONSISTING OF SULFONIC AND PHOSPHORUS THIOIC ACIDS AND THE LITHIUM SALTS THEREOF, (B) FROM 0.1 TO 10.0 EQUIVALENTS OF AN ORGANIC COMPOUND SELECTED FROM THE CLASS CONSISTING OF ENOLS, PHENOLS AND ACI-NITRO COMPOUNDS AND THE LITHIUM SALTS OF SAID COMPOUNDS, (C) A BASICALLY REACTING INORGANIC LITHIUM COMPOUND IN AN AMOUNT SUCH THAT THERE IS PRESENT IN THE MASS SUBSTANTIALLY MORE THAN ONE EQUIVALENT OF LITHIUM, INCLUDING THE LITHIUM PRESENT ONE EQUIVALENT OF LITHIUM, INCLUDING THE LITHIUM PRESENT IN THE REMAINING COMPONENTS, PER EQUIVALENT OF (A) PLUS AND EVAPORATING THE WATER FROM THE MASS TO FORM A LITHIUM COMPLEX, AND THEN BUBBLING CARBON DIOXIDE INTO THE MASS TO LIBERATE A SUBSTANTIAL PROPORTION OF THE ORGANIC COMPOUND OF (B) FROM ITS LITHIUM SALT. 